.TH std::experimental::ranges::not_equal_to 3 "2024.06.10" "http://cppreference.com" "C++ Standard Libary"
.SH NAME
std::experimental::ranges::not_equal_to \- std::experimental::ranges::not_equal_to

.SH Synopsis
   Defined in header <experimental/ranges/functional>
   template< class T = void >

       requires EqualityComparable<T> ||
                Same<T, void> ||                                            (ranges TS)
                /* == on two const T lvalues invokes a built-in operator
   comparing pointers */

   struct not_equal_to;
   template<>                                                               (ranges TS)
   struct not_equal_to<void>;

   Function object for performing comparisons. The primary template invokes operator ==
   on const lvalues of type T and negates the result. The specialization
   not_equal_to<void> deduces the parameter types of the function call operator from
   the arguments (but not the return type).

   All specializations of not_equal_to are Semiregular.

.SH Member types

   Member type                                                       Definition
   is_transparent (member only of not_equal_to<void> specialization) /* unspecified */

.SH Member functions

   operator() checks if the arguments are not equal
              \fI(public member function)\fP

std::experimental::ranges::not_equal_to::operator()

   constexpr bool operator()(const T& x, const   \fB(1)\fP (member only of primary
   T& y) const;                                      not_equal_to<T> template)
   template< class T, class U >

       requires EqualityComparableWith<T, U> ||
                /* std::declval<T>() ==
   std::declval<U>() resolves to                 \fB(2)\fP (member only of not_equal_to<void>
                   a built-in operator comparing     specialization)
   pointers */

   constexpr bool operator()(T&& t, U&& u)
   const;

   1) Compares x and y. Equivalent to return !ranges::equal_to<>{}(x, y);.
   2) Compares t and u. Equivalent to return !ranges::equal_to<>{}(std::forward<T>(t),
   std::forward<U>(u));.

.SH Notes

   Unlike std::not_equal_to, ranges::not_equal_to requires both == and != to be valid
   (via the EqualityComparable and EqualityComparableWith constraints), and is entirely
   defined in terms of ranges::equal_to. However, the implementation is free to use
   operator!= directly, because those concepts require the results of == and != to be
   consistent.

.SH Example

    This section is incomplete
    Reason: no example

.SH See also

   not_equal_to function object implementing x != y
                \fI(class template)\fP

.SH Category:
     * Todo no example
